Calendar: 1884-1885 Page 675

APPLIED SCIENCES 669 Name three metallic minerals and state their chemical composition What is the scale of hardness and how is it applied Give short account of the structure fracture and optical characters of minerals in general State localities in Great Britain where gold silver and tin ores occur and allude to the paragenesis of the latter Show that the streak is useful guide in determining species How would you obtain the specific gravity of sand and also of piece of pumice stone in an unpowdered condition Refer to the cleavage of galena fluor spar and rock salt and add any remarks on these substances which may occur to you Define pseudomorph and twin crystal 10 Take the specific gravity of the specimen placed upon the table and show the steps by which you arrive at the result XII -Ci emt$tvn To what useful purposes are the following substances applied respectively sodium thiosulphate-sulphurous acid -hydrofluoric acid-carbonic oxide How is H2S prepared What change occurs in its solution when kept for some time Sulphur is sold in the forms of roll sulphur-flowers of sulphur--rock sulphur-milk of sulphur how is each of these obtained How is chloride of lime made Why does it become wet when kept for some time in an open vessel What are the chief methods employed for preventing of consuming coal-smoke Give directions for making 100 grammes of strongest nitric acid How many litres of air are required for the complete combustion of 10 grammes of benzene C6H6